I keep getting billed for the same settled account

Worst service ever. I was owing an account. I paid it through Timrisk. Then they send me debit order request via sms. I call they can't see it and I shouldn't worry. I get sms for 2 months. I request paid up letters.Then Timrisk start calling saying I owe the same account that I paid with a different reference number and then I get sms saying I must pay a debit order. And numerous calls. I have emailed the parties involved the information. GETBEEXT***, TRM***7, TRM***8, SA00/126036.